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PRACTICAL ORGANIC CHEMISTRY

methyl alcohol, and the mixture heated on the water-bath for
two hours with an upright condenser. The liquid is then distilled.
with a thermometer. When the temperature rises to 100 the
receiver is replaced by a beaker, and the water-jacket of the
condenser removed. The thermometer rises rapidly to the
boiling-point of methyl oxalate, 160  165, and the distillate
solidifies in the receiver. It is drained at the pump and dried.
It may be recrystallised from spirit. Yield, 2025 grams.

s. Colourless plates ; m. p. 54 ; b. p. 163.
Reactions. m this purpose the alcoholic mother liquor from
the crystals may be used.

1.  Add a little caustic potash solution.    Crystals of potassium
oxalate are deposited.    The ester is hydrolysed.

2.  Add  a few drops  of concentrated  ammonia.     A white
crystalline precipitate of oxamide is formed, C9O.>(OCH3).>-i-

PREPARATION 27.
Glyoxylic Acid, CHO.COOH + H2O.
Glycollic Acid, CH2OH.COOH.
Tafel and Friedrichs, Ber.^ 1904, 37, 3187 ; Centralblatt ; 1905
II, 1699.
20 grms. oxalic acid (in fine powder).
100 c.c. sulphuric acid (10 per cent.).
The process is one of electrolytic reduction and the apparatus.
is similar to that shown in Fig. 77, p. 144. It consists of a smstll
porous cell (8 cm. x 2 cm. diam.) surrounded by a narrow beal<cr
(n cm. x 6 cm. diam.). The oxalic acicl, mixed with 100 c.e.
10 per cent sulphuric acid (titrated against standard baryUt
solution) forms the cathode liquid and is placed in tin-
beaker. The porous cell is filled with the same strength of
sulphuric acid and forms the anode liquid. The electrodes rtrcr
made from ordinary clean sheet lead. The anode consists of ;i
thin strip projecting about two inches from the cell and tlic